1. Field of the Invention
The invention relates generally to devices for photographically reproducing originals and, more particularly, to improved apparatus for developing diazo type films.
2. Description of the Prior Art
Information storage in the form of micro-images on microfilm or microfiche cards has become quite commonplace. As a result, a need has arisen to provide machines for duplicating such micro-images quickly and with relatively inexpensive apparatus. The ammonia-diazo process wherein diazo type film is developed in an ammonia atmosphere in the presence of heat is readily adaptable to such apparatus.
Several machines for developing diazo type films are known. Such machines generally employ apparatus for heating the diazo film in an ammonia atmosphere to effectuate development. The heating of the diazo film is generally accomplished by radiation or convection. When radiation heating is employed, the film is placed in close proximity to a source of radiant energy to be heated by the radiant energy striking the film. When convection heating is employed, the ammonia is heated and the heat from the heated ammonia atmosphere is used to heat the diazo film.
While these techniques provide a way to develop diazo type film, machines employing these techniques generally have a large thermal mass and, consequently, have a long warm up time. Because the diazo film is indirectly heated, the time required to develop the film is also relatively long.